Coupling of Electron and Magnetic Ion Spin in Quantum Dots by Electron-Electron Interaction

Abstract

We have presented a microscopic model of interacting electrons with a magnetic ionspin localized in the centre of a self assembled quantum dot. We have found that theelectrons occupying finite angular momentum orbitals interact with the localizedspin through an effective exchange interaction mediated by electron-electroninteractions. With a localized spin placed in the centre of the dot, only the spins ofelectrons occupying the zero angular momentum states of the s, d, shells coupledirectly to the localized spin via a contact exchange interaction. The effectiveinteraction for p-shell electrons is obtained using exact diagonalization of themicroscopic Hamiltonian as a function of the number of electronic shells, shellspacing and anisotropy of the exchange interaction. The anisotropy of exchangeinterpolates between the interaction types characteristics for conduction bandelectrons and valence band holes. The obtained results were found in goodagreement with previously obtained results